Abrasive wheel drive



Jan. 9, 1951 w, BQ|E 7 2,537,394

ABRASIVE WHEEL DRIVE Filed Aug. 10, 1948 gwwwa m W W Patented Jan. 9, 1951 UNITED A ENT OFFICE William B. Boice, Toledo, Ohio, assignoi-itoBoiee- Crane Company, .Tole'do, (ehio, a corporation of Application August 10, was, SerialNo. 4339's 2 Claims. 1

This invention relates to approximating ciniformity in use of a variable diameter wo'i k ing tool, having to do not only with rotative speed but work treatment.

This invention has utility when incorporated in a Wet-grinder, wherein there is a peripheral drive for the abrasive element or wheel, and diameter reduction com ensation controls for rel'ooatin'g the element and the work to be upon.

Referring to the drawings:

Fig. 1 is a side elevation of an embodiment of the invention in a bench type of wet grinder, parts being broken away.;

Fig. 2 is an end elevation from the right of Fig. 1, with some portions removed; and

Fig. 3 is a partial plan view of unit of Fig. 1.

Upon a bench screws 2 may anchor sheet metal feet or brackets 3 as weld-assembled with a receptacle or vessel 4 adapted to retain a cutting promoting substance or water 5. Set screws 6 provide for mounting a removable lid or cover 1 on the open top of the vessel 4.

A base 8 on the bench provides support for a prime mover or electric motor 9 having on its shaft H! a pulley II for a V-type belt |2 to a driven pulley l3 fixed by a set screw M with a shaft l5. The shaft I has bearings It in a U- bracket ll swingable on a bearing pin l8 mounted by parallel cheek portions or flanges |9 rising from the lid 1 about an opening 20. A cover 2| spanning between the pin H3 and the shaft l5 forms a partial shield 22 over a friction drive rubber faced roller 23. The roller 23 is yieldably held to peripherally engage abrasive disk or grinding element 24 upwardly protruding from the opening 20 between the flanges |9. A torsion spring 25 having its ends 26 engage the flanges l9 and with spring wraps about the pin l8 has a medial loop 21 engaging the underside of the cover 2|, thereby urging the roller 23 against the grinder 24. 1

The grinder wheel 24 is rotatably mounted on a shaft 28 with flattened end portions 29 engaged by externally threaded stems 30 thru slots 3| in the lid 1 adjacent the flanges I9. The slots 3| are parallel to each other and later-ally to a radius to the shaft l5. Adjusted proximity for efficient contact between the driving friction roller 23 and the driven disk 24 is determined and caps 32 on the stems 30 clamp lock the disk 24 against shifting therefrom during operation.

Inasmuch as the disk 24 is of approximately uniform abrasive body thruout and the use fil -134:5)

gradually wears off small particles to reduce its effective or working diameter, the resetting permitted thru "the slots 3| may be undertaken in compensation for wearing down the wheel 24. Inasmuch as the drive roller 23 has peripheral contact, this means that, even tho the diameter of the work engaged wheel 24 may be reduced, lineal peripheral speed will be maintained. Watches 33 in the flanges is "provide elearance for the shaft 1 5 to swln'gdownward m taining its frictional driving "contact with the disk 24.

Remote from the notches 33, the flanges 4-9 have a higher shield portion 34 about the wheel 24, with downwardly and inwardly or toward the notches 33, :a pair of "slots 35 parallel'to inclined top edge portions 36 extending to the flange portions #9. For each slot' fi there is an angle plate 31 down flange inside the slot 35 with an outwing 38 therefrom to ride clear of the edge 35 and provide a bearing 39 for a relatively rockable work rest or support upon which objects to be dressed or treated may be steadied in being held and directed by the operator for the work to be in engagement with the disk 24. A pair of depending arc flanges 40 from the inner sides of the legs of the U-shaped rest 4|, have clearance 42 as to the bearing 39 and arc slots 43 spaced by the shield 34 from the plate 31. Offsets or lugs 31' from the plate 31 ride in the slot 35 and hold the plate 31 from tilting.

From a head 44 on a pin 45 in the opening 20 side of the plate 31, the pin 45 extends thru and is held fixed with the plate 37 and the slot 35 fixed with the vessel lid 1 and on thru the arc slot 43 fixed with the tool rest 4|. A clamp washer 46 on the pin 45 may be set by a win nut 41 having threaded engagement with the pin 45. There is thus provided here a full range for tool rest rock adjustment. Slacking of a nut 41 from a clamp washer 41" loosens up to permit movement of the pin 45 inward along the slot 35 to have take-up as the disk 24 has its diameter become less from wear. Furthermore, outward adjustment may be had, say upon insertion of a new wheel 24, or to take care of special rest positions for a desired type of work support. The adjustments last described have to do with merely sliding along the slot 35, without any relative movement between the flanges 49 and the pins 45. In order to vary the top plane or side of the rest 4|, as to the approach thereof to the peripheral face of the disk 24, when the wing nuts 41 at each side are loosened, the free end edge of the rest 4| may be pushed downward, or lifted upward to gain the desired pitch or slant. In this operation, the slots 43 of the flanges 40 move relatively to the pins 45 and the washers 57'. Upon locking of the work rest 4|, the wingnuts 4T pull the heads 44 to cause the plates 3'! to frictionally grip the inner sides of the shield 34 at the slots 35, while simultaneously the clamp washers 46 grip the flanges 48 in the vicinity of the slots 43 against the outer faces or sides of the shield 34.

Arrow 48 indicates the direction of rotation of the abrasive element 24, herein shown as clockwise (Fig. 1). This means that the friction driving roller 23 has a counterclockwise direction of rotation. The firm driving relation of the roller 23 on the element 24 seemsto reduce the liquid to a film spread condition and minimizes tendency to have such thrown toward the operator. The down direction reach indicated by arrow 49 for the belt l2 in conjunction with the spring 25 establishes a practical holding-in or driving relation for the roller 23 with the element 24.

What is claimed and it is desired to secure by Letters Patent is:

1. In a wet grinding apparatus, a tank adapted to contain liquid, a rotary grinding wheel, means for so mounting the wheel that a portion thereof extends into the tank and a portion projects above the tank, a work holder mounted adjacent the periphery of the grinding wheel, and friction drive means adapted to rotate said grinding wheel to cause a peripheral portion thereof to pass through the liquid to wet the same and to advance the wetted surface toward the work holder, said driving means including a friction 3 roller adapted to engage the wetted surface of said wheel as it rises from the liquid in the tank in advance of the work holder, whereby the roller serves the dual function of actuating the grinding wheel and of removing excess moisture from the rising surface of the wheel before it reaches the work holder.

2. A grinding apparatus as set forth in claim 1, wherein the friction roller is carried by a hingedly mounted bracket at a position remote from the bracket hinge, whereby the frictional contact between the roller and grinding wheel is aided by gravity.

WELIAM B. BOICE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 136,939 Richardson Mar. 18, 1873 367,331 Barnes July 26, 1887 498,623 Clock May 30, 1893 504,329 Clapp Sept. 5, 1893 516,353 King Mar. 13, 1894 538,331 Hyde 'Apr. 30, 1895 618,293 Ridley Jan. 24, 1899 656,171 Clapp Aug. 21, 1900 763,635 Rexroth June 28, 1904 1,185,182 Davis May 30, 1916 1,824,000 Walter Sept. 22, 1931 2,092,714 Flygare Sept. 7, 1937 2,228,386 Burns Jan. 14, 1941 2,444,598 Eyles July 6, 1948 FOREIGN PATENTS Number Country Date 476,655 Germany May 2, 1929 

